Hitting a baseball isn't the most difficult activity in sports—changing a long-standing culture is. For many years, a player was not officially diagnosed with a concussion unless there was a loss of consciousness. That started to change a few decades ago, but the physiological causes and long-term effects of concussions still were not fully understood. Thus, practices among players and non-medical personnel remained static.

It was almost as if concussions were not a part of the game of baseball except in the rarest of cases—they were considered nearly exclusive to the NFL, where raw power and violence reigned, or to the NHL, where speed and power dominated. If you have been paying attention to baseball over the last decade, you know this is not the case. Players were suffering concussions that were originally thought to be mild before suffering from post-concussive syndrome for weeks or months.

Gradually, concussions began to garner more attention until they finally reached a fever pitch following a perfect storm of negative news. Several former NFL players suffered from physiological brain changes prior to their deaths, and the tragic cases of young people taking their own lives following concussions had everyone paying more attention to the injury. A report in the summer of 2010 suggested a possible connection between multiple concussions and amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease. Even though there were questions raised about that study, what was happening on the diamond raised even greater concern.

Three players–Justin Morneau, Jason Bay, and Jason LaRue–all suffered season-ending concussions (in the case of LaRue, it was a career-ending one). People within baseball started planning on changes several years ago, but the rash of concussions led them to fast-track their efforts. In late March of 2011, MLB and the MLBPA reached a historic agreement governing all aspects of concussion evaluation and treatment. The major points that were agreed upon included:

Mandatory neuropsychological pre-season testing using the ImPACT system. These computerized tests, developed by doctors Mark Lovell and Joseph Maroon in the early 1990s, take roughly 20 minutes to complete and provide objective measurements across several characteristics, including memory, reaction time, cognitive function, and impulse control. While the system can be used without a baseline, it is most effective when one is able to compare a test score after a concussion to a pre-concussion baseline, since everyone's baseline is different. Most clubs already do this, but now it is mandatory.

Protocols for the evaluation of potential concussions among players and umpires were created. Based on recommendations by the National Athletic Trainers Association (NATA) in a position statement, these protocols are to be used for any high-risk incidents. Obvious activities include being beaned, hit by a batted ball, or collisions with a player, umpire, or fixed object, in addition to any time the head is forcibly rotated, in order to account for those indirect forces capable of producing a concussion. An important element of these protocols is the league-wide adoption of a sideline assessment tool called, surprisingly enough, the sport concussion assessment tool (SCAT2), which is also used by organizations such as FIFA and the Olympics.

The creation of a seven-day disabled list specifically for concussions. There has never been a disabled list for one particular injury before, and the length of the term is important, as we will discuss later.

The creation of standardized protocols for clearing anyone to return to play. The medical qualifications have remained constant for some time based on the same NATA position statement, in terms of absence of symptoms and progression of activities. Now they are standardized, and a return-to-play form must be filled out and submitted to the MLB medical director for players with concussions, regardless of whether the player in question was placed on the disabled list. The team must also name an MTBI specialist in the home city, in case any further evaluation is needed.

Everyone agrees that this is an important step for the long-term health of the players and umpires, but its implications haven't been fully explained from a medical standpoint.

Concussions are not just the symptoms that people experience; they also include biochemical changes that occur rather rapidly. There has been a lot of attention paid to the chemical changes inside the brain following concussions—and rightfully so. These changes can lead to horrible long-term effects that are irreversible (for now), but even more importantly, they cannot be easily observed.

These changes don't show up in normal diagnostic imaging techniques such as MRIs, X-rays, or CT scans, as they are more suited for severe traumatic injuries like skull fractures or bleeding inside the brain. These more serious injuries still need to be ruled out, so it's not like you should avoid the emergency rooms, but concussions are not like broken bones, where the effects are immediately visible. You can't “see” a concussion with normal imaging.

Computerized testing is akin to a diagnostic test that allows you to “see” a concussion. The ImPACT system can take the baseline measurements from the preseason and compare them to a repeat test following a suspected concussion. It creates several objective measurements and reveals how close brain function has come to returning to that particular person's normal level.

Why is the baseline test so important? Just like any other test, the results of a single test are open to interpretation. Two doctors often have differing opinions on an MRI and the timeframe for recovery; further testing is often performed. If the person has multiple MRIs over a course of time, the chances of differing opinions significantly decrease. Similarly, a single ImPACT test after an injury can also be open to discussion—does the player have a bad memory, or is he concussed? When combined with baseline testing, the results become clearer and a better management plan can be initiated, whether it involves the introduction of medication or of gentle exercise.

The next major point that everyone is discussing is the introduction of new protocols based off of the NATA concussion position statement. It seems like this would provide a major change in the quality of health care provided, but, in reality, it won't. The position statement was created by a team of expert athletic trainers and physicians before it was published in the Journal of Athletic Training in 2004. For sports medicine staffs, this position statement is the basis for all on-field or sideline evaluation of concussions, and it covers everything from assessing concussions to special considerations for younger athletes.

This section of the new MLB policy–including the adoption of the SCAT2 tool that consists of several mini-tests to quickly assess brain function–standardizes what has already been in place and eliminates any interpretation of the rules for “special” cases.

The creation of a seven-day disabled list is likely going to be one of the most influential changes created by this policy. It allows the team the right, but not the obligation, to disable a player with a concussion for seven days, rather than the standard minimum of 15.

We saw this in action with the mild concussion that caused Yunel Escoba to miss a few games. It was assumed that once he was diagnosed with the concussion, he would automatically have to be placed on the new disabled list. The committee realized that this would lead to more vague diagnoses that could attempt to skirt the rule rather than making the proper medical diagnosis of a concussion. The seven-day length is crucial and is based on academic research showing that most average concussions clear within five to seven days. This number does not include major concussions, like the ones suffered by Justin Morneau and Jason Bay.

Our database, which does include all concussions, shows that for position players who have returned in the same season, the average number of games missed is eight, while for pitchers it is 26. Even though there are significantly fewer cases of concussed pitchers than hitters in our database, the number of games missed is dramatically different.

The leading reason for this isn't the number of concussions or the “type” of concussion, but the differences in head protection at the time of the concussion. More research is coming out that suggests that in the absence of severe trauma such as a skull fracture, a sudden rotational force produces more severe and long-lasting concussions, all else being equal. All else isn't equal between hitters and pitchers. Hitters have a helmet on for the majority of their concussive episodes, while pitchers never do when they are on the mound. As a result, much more force is being transmitted through the skull with pitchers. Therefore, while pitchers would in most cases end up on the 15-day disabled list anyway, hitters have been stuck in the “hurt, but not quite hurt enough” zone. The creation of this seven-day disabled list provides teams with a way to insure themselves for the eight days between disabled list transactions.

The standardization of return-to-play protocols is another way to ensure that the pressures from the player, other players, management, fans, agents, and others don't end up putting the player into a position where he returns too early. Players need to be on the field to prove themselves worthy of their next contract, and they have been known in the past to understate their symptoms in order to get on the field earlier. The new return-to-play protocols will protect the players from everyone—including themselves.

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